One loop out of Chamonix, France, circumnavigating the Mont-Blanc massif through Italy and Switzerland and back, crossing 4 UTMB personal-assistance stations (Les Contamines, Courmayeur, Champex-Lac, Vallorcine) among 14 named checkpoints and 18 total waypoints on the official Time Chart.
Numbers that do not reconcile, recorded rather than resolved: the race page banner and the Runner's Guide cover both give 174km / 9,900m D+; the guide's own body text on the UTMB race page instead says "171kms of trails and 10,000m of D+"; the website's underlying GPX-derived track stats give 176.865km / +10,000m / -9,999m; and the guide's own official TIME CHARTS table sums to 177.6km / +9,737m / -9,733m at the finish line -- all four are 2026-edition, non-archival numbers from the same organizer within the same document set. distance_miles and elevation_gain_ft/elevation_loss_ft here use the TIME CHARTS total (the operational pacing document, same precedent as Western States' checkpoint chart over its FAQ); published_distance_value/published_gain use the headline banner figure. The TIME CHARTS table itself has one internal anomaly: cumulative D+ is printed as 9,937m at La Flegere (km 170.6) then 9,737m at the Chamonix finish (km 177.6), a 200m DECREASE, which is not possible for a true running cumulative-gain column (the matching D- column is perfectly monotonic end to end). leg_climb_ft for that final leg is left null rather than publish a fabricated or negative number. The organizer itself notes: "the course (distance and elevation gain) may be adjusted depending on terrain constraints."
The UTMB is the headline 100-mile race of HOKA UTMB Mont-Blanc week: a single-stage loop out of Chamonix that circumnavigates the Mont-Blanc massif through France, Italy and Switzerland, roughly 170-178km with about 9,900-10,000m of climb, crossing 18 towns above 2,500m at its high points. It is the 100M final of the UTMB World Series.
Created in 2003. Per the race's own framing: "the most mythical and prestigious trail running race in the world", won in as little as ~20 hours or as long as the 46:45 time limit allows, by elite and amateur runners on the same course.
| Mile | Station | Cutoff | Crew | Bag | Pacer | Med | To next |
|---|---|---|---|---|---|---|---|
| 0.00 |
Chamonix
3,422 ft
|
? | ? | ? | ? | ● | 5.72 |
| 5.72 |
Les Houches
3,317 ft
|
? | · | · | ? | ● | 8.51 |
| 14.23 |
Saint-Gervais
2,661 ft
|
10:00pm | · | · | ? | ● | 6.03 |
| 20.26 |
Les Contamines
3,816 ft
|
12:00am | ● | · | ? | ● | 2.73 |
| 22.99 |
Notre Dame de la Gorge
3,980 ft
|
? | ? | ? | ? | ? | 2.67 |
| 25.66 |
La Balme
5,614 ft
|
2:00am | ? | ? | ? | ? | 2.36 |
| 28.02 |
Col du Bonhomme
7,644 ft
|
? | ? | ? | ? | ? | 1.25 |
| 29.27 |
Refuge de la Croix du Bonhomme
8,035 ft
|
? | ? | ? | ? | ? | 3.29 |
| 32.56 |
Les Chapieux
5,072 ft
|
5:15am | · | · | ? | ● | 6.71 |
| 39.27 |
Col de la Seigne
8,241 ft
|
? | ? | ? | ? | ? | 1.68 |
| 40.95 |
Col des Pyramides Calcaires
8,422 ft
|
? | ? | ? | ? | ? | 3.35 |
| 44.30 |
Lac Combal
6,434 ft
|
10:00am | · | · | ? | ● | 1.74 |
| 46.04 |
Arete du Mont Favre
7,995 ft
|
? | ? | ? | ? | ? | 2.86 |
| 48.90 |
Checrouit - Maison Vieille
6,404 ft
|
? | · | · | ? | ● | 3.11 |
| 52.01 |
Courmayeur Forum Sport Center
3,927 ft
|
1:15pm | ● | ● | ? | ● | 3.42 |
| 55.43 |
Refuge Bertone
6,486 ft
|
? | · | · | ? | ● | 4.72 |
| 60.15 |
Refuge Bonatti
6,640 ft
|
? | ? | ? | ? | ? | 3.23 |
| 63.38 |
Arnouvaz
5,860 ft
|
6:15pm | · | · | ? | ● | 2.92 |
| 66.30 |
Grand Col Ferret
8,320 ft
|
? | ? | ? | ? | ? | 2.24 |
| 68.54 |
La Peule
6,801 ft
|
? | ? | ? | ? | ? | 3.97 |
| 72.51 |
La Fouly
5,256 ft
|
10:30pm | · | · | ? | ● | 5.04 |
| 77.55 |
Praz de Fort
3,789 ft
|
? | ? | ? | ? | ? | 3.54 |
| 81.09 |
Champex-Lac
4,829 ft
|
2:30am | ● | ● | ? | ● | 3.04 |
| 84.13 |
Plan de l'Au
4,386 ft
|
3:45am | ? | ? | ? | ? | 4.17 |
| 88.30 |
La Giete
6,171 ft
|
? | ? | ? | ? | ? | 3.10 |
| 91.40 |
Trient
4,288 ft
|
8:00am | · | · | ? | ● | 2.49 |
| 93.89 |
Les Tseppes
6,381 ft
|
? | ? | ? | ? | ? | 5.03 |
| 98.92 |
Vallorcine
4,154 ft
|
11:15am | ● | · | ? | ● | 2.92 |
| 101.84 |
Col des Montets
4,685 ft
|
? | ? | ? | ? | ? | 1.12 |
| 102.96 |
Tete de Bechar
5,600 ft
|
? | ? | ? | ? | ? | 3.05 |
| 106.01 |
La Flegere
6,227 ft
|
2:45pm | · | · | ? | ● | 4.35 |
| 110.36 |
Chamonix
3,425 ft
|
4:30pm | ? | ? | ? | ● | ? |
Do not drive here: road and parking closures during the event make Les Contamines, Courmayeur, La Fouly, Champex and Vallorcine unreachable by private car. Crew must buy a paid UTMB Mobility shuttle pass (sold 09/06-12/07/2026 only, no on-site sales) and book a departure slot; the only stated exceptions are people with disabilities, families with children under 3, and support crews for top-elite runners.
montblanc.utmb.worldDo not drive here: road and parking closures during the event make Les Contamines, Courmayeur, La Fouly, Champex and Vallorcine unreachable by private car. Crew must buy a paid UTMB Mobility shuttle pass (sold 09/06-12/07/2026 only, no on-site sales) and book a departure slot; the only stated exceptions are people with disabilities, families with children under 3, and support crews for top-elite runners.
montblanc.utmb.worldDo not drive here: road and parking closures during the event make Les Contamines, Courmayeur, La Fouly, Champex and Vallorcine unreachable by private car. Crew must buy a paid UTMB Mobility shuttle pass (sold 09/06-12/07/2026 only, no on-site sales) and book a departure slot; the only stated exceptions are people with disabilities, families with children under 3, and support crews for top-elite runners.
montblanc.utmb.worldDo not drive here: road and parking closures during the event make Les Contamines, Courmayeur, La Fouly, Champex and Vallorcine unreachable by private car. Crew must buy a paid UTMB Mobility shuttle pass (sold 09/06-12/07/2026 only, no on-site sales) and book a departure slot; the only stated exceptions are people with disabilities, families with children under 3, and support crews for top-elite runners.
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